General Relativity is the local gauging of the four-parameter translation group T4, but the four spin 1 tetrads are the natural compensating gauge potentials not the spin 2 graviton second rank tensor metric field's Levi-Civita-Christoffel connection components. In all the quantum gravity schemes 't Hooft describes the tetrads are not mentioned.
"A point made repeatedly by this author is that it is quite likely, at least philosophically
more acceptable, that the quantum properties of black holes are indeed sharply defined
by some theory."
"It would be premature to assert that this would be at odds with general
relativity. That would involve assumptions concerning behavior of matter near the
Planck scale, and such assumptions nay be suspected to be wrong. Ingoing particles that
encounter outgoing ones at a Planckian distance away from the horizon do indeed influence
them, while passing through. If not the ordinary standard model interactions perturb the
outgoing particles, then certainly the gravitational force, due to graviton exchange, will do
the job. But the job done by gravitons is difficult to compute: it diverges."
"It was attempted to make the next step: compute such effects. To some extent we
succeeded in obtaining a unitary scattering matrix for black holes, but its Hilbert space
still contained more states than allowed by the value (5.6) as dictated by the entropy.
The only way to obtain the correct density of states appears to be by assuming that
there really are no more states to be discussed than just that number. By itself, this
appears to be an interesting and physically meaningful piece of information: the number
of mutually orthonormal states to be employed in the description of the horizon of a black
hole is limited by Eq. (5.6)."
"But its consequences are far-reaching: these states seem to be
distributed at the horizon, which is a two-dimensional plane. Yet the states one started off
with, using general coordinate transformations to describe the properties of a black hole
once the properties of the vacuum world experienced by a local observer near the horizon
are understood, appear to be distributed in a three-dimensional space!"
"This led us to formulate the so-called ‘holographic principle’:
The complete set of degrees of freedom for all particles populating a certain region
in space and time, can be represented as if they were all situated on the boundary
of this space-time. Roughly, there is one Boolean degree of freedom for every
4 ln 2 Planck lengths squared.
This complete rearrangement of the physical degrees of freedom in the theory of quantized
particles in the Planck regime, has far reaching implications for this theory. It invalidates
the unusual distinction between intensive and extensive variables. Usually, extensive variables such as total mass, charge and energy may be seen as integrals of the corresponding
densities over three-space. This will no longer be true; most integrations will be over some
"When we arrived at the holographic principle, we took this surface to be
the horizon of a black hole, but for a local observer this surface would be indistinguishable
from any other surface. Thus, one must conclude that the physical degrees of freedom may
be projected onto any (infinite) surface at any time in three-space."
Obviously not any surface will do. Horizons are different because static LNIFs outside the black hole horizon need infinite acceleration at the horizon to stand still and they are destroyed by "infinite" temperature black body radiation. Of course the coincident LIF will not see those black body photons.
"In several cases, the violation of Bell’s inequalities was verified experimentally. Any hidden
variable theory that cannot accommodate these facts must be discarded. The remainder
of this paper will describe the present author’s approach in more detail. Although it is not
clear how violations of Bell’s inequalities can come about in this theory, it is also difficult to
prove that they cannot be violated."
't Hooft does not mean Bohm's hidden variables.
"The cosmological constant in the real world seems to be extremely accurately tuned
to zero, whereas the only known mechanism that might be related, supersymmetry, is
strongly violated. How can a crippled symmetry produce a cancellation over 120 orders of
't Hooft's paper was written in 2000 before he knew about dark energy and he does not associate the dark energy density with the inverse area-entropy of our future horizon. Indeed, back then he did not even know there was such a future horizon with which to apply Yakir Aharonov's idea of post-selection.
"Cosmologists have long been puzzled about why the conditions of our universe—for example, its rate of expansion—provide the ideal breeding ground for galaxies, stars, and planets. If you rolled the dice to create a universe, odds are that you would not get one as handily conducive to life as ours is. Even if you could take life for granted, it’s not clear that 14 billion years is enough time for it to evolve by chance. But if the final state of the universe is set and is reaching back in time to influence the early universe, it could amplify the chances of life’s emergence."
On Dec 13, 2010, at 12:45 PM, JACK SARFATTI wrote:
On Dec 13, 2010, at 12:35 PM, Paul Zielinski wrote:
"I don't get it. Why can't we say that the Born interpretation works, except when it doesn't? That it applies
contingently in case unitarity holds, but not otherwise?"
That is what I say. Antony Valentini's Bohmian model shows it explicitly formally.
Also, even in my original back-reaction idea of 1996 given at Tucson II (abstract in their proceedings)
For simplest toy model of a single particle in a box
Bohm's post-quantum potential is Q*(X,x) where X is the coordinate of the actual particle and x is the variable covering the whole box.
In ordinary QM with unitarity we only have Q(x) no X-dependence i.e. action of Q on particle X without any direct back-reaction of X on Q.
"It's not hard to come up with examples from classical physics where a stochastic variable is associated
with a wave disturbance. The wave disturbance evolves deterministically, while the probability distribution
for the associated stochastic variable passively reflects the effect of the wave disturbance. In such cases
the nature of the probability distribution has no bearing on the underlying wave phenomenon, which is
determined independently of whatever statistical distribution is derived from it.
Why can't the Born interpretation be understood in the same way?
Isn't this the tail wagging the dog?"
On Mon, Dec 13, 2010 at 11:11 AM, JACK SARFATTI wrote:
On Dec 13, 2010, at 2:38 AM, Google Alerts wrote:
Web 1 new result for Gerard 't Hooft
"Fun with big numbers" | Myspace Forums
This may help: Gerard 't Hooft OBSTACLES ON THE WAY TOWARDS THE QUANTIZATION OF SPACE, TIME AND MATTER www.phys.uu.nl/~thooft/gthpub/foundations.pdf ...
"The theory of Quantum mechanics and Einstein’s theory of general relativity have been equally successful. Both are based on principles that are assumed to be exactly valid: quantum mechanics requires a hermitian hamiltonian to describe the evolution of vectors in a Hilbert space. Hermiticity is mandatory in order to ensure the conservation of probabilities, and giving up the probabilistic interpretation of the wave function would imply a big departure from the (highly successful) first principles of quantum mechanics. General relativity is based on invariance under general coordinate transformations. Any violation of the principle of coordinate invariance would imply the existence of some preferable set of coordinates of a kind never observed in Nature.
Thus, what these two theories have in common is that small deviations from their principal starting points cannot be tolerated since these would invalidate the underlying logic; the starting points must be exactly valid. The theories also have in common that they allow large varieties of secondary ‘laws of Nature’: in quantum mechanics, we could call the Schr ?odinger equation the primary law; the secondary laws of Nature here are the ones that determine the interaction potentials and coupling strengths. In general relativity, Einstein’s equation for the gravitational field is the primary equation, but the details of the matter field equations are secondary; they are not prescribed by the theory.
... A theoretical study of black holes leads to the so-called holographic principle ... Superstring theory claims some successes in reproducing the requirement of holography to its heaviest (black hole) states, at the cost of a very indirect physical interpretation of its foundations. This author tends to be more and more inclined towards the suspicion that the problems of quantum gravity are much more than purely technical ones; they touch upon very essential philosophical issues."
Gerardus introduces the temporal gauge, which requires zero geomagnetism, i.e. g0i = 0, i = 1,2,3. This is no good as it does not permit the Kerr solution, nor even the Rindler horizon solution for a uniformly accelerating frame in Minkowski spacetime. For example, see Ray Chiao's papers on EM-GW transducers.